Office of Research & Economic Development

Biology may affect political leanings

Why does it seem many people begin with political preferences and then try to find reasons justifying their inclinations? Why is it so difficult to sway people who care deeply about politics no matter how compelling the facts or persuasive the prose? University of Nebraska-Lincoln research may help to answer these questions.

By monitoring people's physical sensitivities to things like sudden noises and threatening visual images, political scientists were able to conclude that physiological reactions help predict variations in political beliefs.

For the first time, political scientists show that people who are physiologically highly responsive to threat are likely to advocate policies that protect against threats to the social unit: favoring defense spending, capital punishment, patriotism and the Iraq War. In contrast, people who are less startled by sudden noises and threatening visual images are more likely to support foreign aid, liberal immigration policies, pacifism and gun control.

Researchers report their discovery in the Sept. 19 issue of the weekly international journal Science. Authors are UNL political science professors John Hibbing and Kevin Smith, UNL psychology professor Mario Scalora, Rice University political science professor John Alford, Virginia Commonwealth University postdoctoral fellow Peter Hatemi, and graduate students Doug Oxley and Jennifer Miller, of UNL, and Matthew Hibbing at University of Illinois-Urbana Champaign.

"What the findings suggest is a different view of the nature of political beliefs than the common understanding that political attitudes are exclusively the result of experiences and the environment," said John Hibbing.

Hibbing's team used physiological testing: skin conductance and eye movement sensors, to assess the body's biological reaction to threatening stimuli. Testing with these psychophysiological procedures is quite unusual in political science, he said.

This study involved a group of 46 people who admitted to caring about political issues. Researchers showed participants threatening visual images — pictures of a very large spider on a person's face, a dazed person with a bloody face and an open wound with maggots in it — and their skin was monitored for electrical conductivity. Hibbing said skin conductance tests indicate emotion, arousal and attention. By using the skin conductance tests, the researchers are able to track a person's reactions to the threatening stimuli.

In another physiological measure, scientists tested the "orbicularis oculi startle blink response" to record the amplitude or intensity of blinks. They surprised subjects with a sudden, jarring noise and measured how hard they blinked in response to being startled.

Researchers compared participants' reactions to the physical testing with their self-reported political attitudes on protective policies. They concluded that participants most disturbed by the threatening stimuli or by loud noises were also most likely to advocate socially protective policy positions.

"Now we can show that certain important political beliefs have a very deep basis," Hibbing said. "We don't know for certain that it's genetic but we do know that there's a predilection biologically that leads some people to experience the world differently from others. The relationships we found are far from deterministic — environmental events still play a vital role — but the fact that physical reactions to loud noises or to scary animals is at all predictive of political beliefs is remarkable.”

“Should extreme interrogation techniques be used on foreign nationals suspected of terrorist activities? Should the privacy of law-abiding citizens be sacrificed if doing so offers the potential for making the country safer? Our research suggests that the answers a person provides to questions such as these are in part traceable to how vividly they physically experience generic threats.”

"And if political beliefs do run as deep as we suggest, it becomes easier to understand why political conflict is so persistent. It's not that those who disagree with us politically are being intentionally stubborn but rather that the world seems very different to them. Perhaps recognition of the deep physical nature of these differences will increase political tolerance and understanding,” Hibbing concluded.

The study, which was supported by National Science Foundation grants, builds on Hibbing's and his colleague's earlier research examining the role of genetics in shaping people's political temperaments and attitudes. His upcoming research, also funded by NSF, will focus on testing the varying brain activation patterns induced by the presentation of threatening images and locating the physiological predictors of political apathy